1. Field of the Invention
This invention relates to improved operating microscopes, that is, to microscopes used by surgeons in performing surgical operations.
2. Related Art
Many thousands of operating microscopes, such as the Zeiss Company's OPMI microscopes, are in use throughout the world. U.S. Pat. No. 4,448,498 to Muller et al. shows such an operating microscope. These microscopes provide a surgeon with a binocular stereoscopic image in which he can observe his surgical implements in the operating field; he can perform the entire operation without looking directly at the subject. The Zeiss OPMI microscopes are optical (that is, provide a real image which is seen in an eyepiece), as opposed to an operating microscope providing a video image on a video screen or the like.
Conventional image enhancement techniques allow one to derive additional information from a visible image. Typically, mathematical techniques such as Fourier transformation are used to enhance or bring out details of the image which are obscured in the unenhanced image.
Such enhancement techniques typically involve producing an image signal responsive to an image of the object using an image sensor such as a charge-coupled device (CCD) image forming element. The image signal is then digitized, for example, using an analog-to-digital converter connected to the CCD image forming element. Data processing equipment and techniques are then used to provide the desired image enhancement. The enhanced image can then be displayed on a video display or the like. Insofar as such conventional image enhancement techniques have been applied to microscopes, the only display provided of the enhanced image has been a video display or the like. Performance of image enhancement tends to obscure the visible "landmarks" used by the surgeon to orient himself with respect to the tissues of the patient.